Timer

Introduction

The VEX IQ (2nd gen)’s brain has a timer that keeps track of elapsed time from the start of a project. It can be used to measure durations, trigger events after a set time, or reset for new timing operations. Below is a list of all available blocks:

• reset timer – Resets the timer to zero.

• timer in seconds – Returns the current elapsed time in seconds.

• when timer – Runs a stack of blocks after the timer exceeds a specified time.

Events

when timer

The when timer block activates the attached stack of blocks after a specified amount of time.

The when timer hat block.

  when timer > [1] seconds :: hat events

Parameters	Description
time	Specifies the number of seconds before the attached stack of blocks starts. Accepts both whole and decimal numbers.

Example

A stack of blocks that begins with a when timer > 2 seconds block, followed by a comment block reading Play a fail after 2 seconds. Once the timer exceeds two seconds, a play sound block plays the fail sound.

  when timer > [2] seconds :: hat events
  [Play a sound after 2 seconds.]
  play sound [alarm v]

Sensing

reset timer

The reset timer block resets the timer to zero.

The reset timer stack block.

  reset timer :: custom-orientation

Parameters	Description
	This block has no parameters.

Example

A stack of blocks that begins with a when started block, followed by a comment block reading Print the time on the screen and reset the time after five seconds. Inside a forever loop, a reset timer block starts the cycle. A while loop runs while the timer is less than or equal to three seconds, repeatedly clearing row 1, setting the cursor, and printing the timer value on the screen.

  when started :: hat events
  [Display the time the robot takes to turn right.]
  drive [forward v] for (200) [mm v] ▶
  reset timer :: custom-orientation
  turn [right v] for (90) degrees ▶
  set print precision to [0.1 v] on [Brain v]
  print [Turn right took] on [Brain v] ◀ and set cursor to next row
  print (timer in seconds) on [Brain v] ▶
  print [ seconds] on [Brain v] ▶
  

timer in seconds

The timer in seconds block returns the elapsed time since the timer was last reset, as a float in seconds.

The timer in seconds reporter block.

  (timer in seconds)

Parameters	Description
	This block has no parameters.

Example

A stack of blocks that begins with a when started block, followed by a comment block reading Display the time after 2 seconds have passed. A wait until block pauses execution until the timer reaches or exceeds two seconds. Once this condition is met, a print block displays the timer value on the screen.

  when started :: hat events
  [Display the time it takes to move in a square.]
  repeat (4)
  drive [forward v] for (100) [mm v] ▶
  turn [right v] for (90) degrees ▶
  end
  set print precision to [0.01 v] on [Brain v]
  print (timer in seconds) on [Brain v] ▶